Ionic Liquid-Solute Interactions Studied by 2D NOE NMR Spectroscopy

Sufia Khatun, Ed Castner

Research output: Contribution to journalArticle

20 Citations (Scopus)

Abstract

Intermolecular interactions between a Ru2+(bpy)3 solute and the anions and cations of four different ionic liquids (ILs) are investigated by 2D NMR nuclear Overhauser effect (NOE) techniques, including {1H-19F} HOESY and {1H-1H} ROESY. Four ILs are studied, each having the same bis(trifluoromethylsulfonyl)amide anion in common. Two of the ILs have aliphatic 1-alkyl-1-methylpyrrolidinium cations, while the other two ILs have aromatic 1-alkyl-3-methylimidazolium cations. ILs with both shorter (butyl) and longer (octyl or decyl) cationic alkyl substituents are studied. NOE NMR results suggest that the local environment of IL anions and cations near the Ru2+(bpy)3 solute is rather different from the bulk IL structure. The solute-anion and solute-cation interactions are significantly different both for ILs with short vs long alkyl tails and for ILs with aliphatic vs aromatic cation polar head groups. In particular, the solute-anion interactions are observed to be about 3 times stronger for the cations with shorter alkyl tails relative to the ILs with longer alkyl tails. The Ru2+(bpy)3 solute interacts with both the polar head and the nonpolar tail groups of the 1-butyl-1-methylpyrrolidinium cation but only with the nonpolar tail groups of the 1-decyl-1-methylpyrrolidinium cation. (Chemical Equation Presented).

Original languageEnglish
Pages (from-to)9225-9235
Number of pages11
JournalJournal of Physical Chemistry B
Volume119
Issue number29
DOIs
Publication statusPublished - Jul 23 2015

Fingerprint

Overhauser effect
Ionic Liquids
Ionic liquids
Nuclear magnetic resonance spectroscopy
solutes
Cations
Positive ions
nuclear magnetic resonance
cations
liquids
spectroscopy
Anions
Negative ions
interactions
anions
Nuclear magnetic resonance
Amides
amides

ASJC Scopus subject areas

  • Physical and Theoretical Chemistry
  • Materials Chemistry
  • Surfaces, Coatings and Films

Cite this

Ionic Liquid-Solute Interactions Studied by 2D NOE NMR Spectroscopy. / Khatun, Sufia; Castner, Ed.

In: Journal of Physical Chemistry B, Vol. 119, No. 29, 23.07.2015, p. 9225-9235.

Research output: Contribution to journalArticle

@article{4b3ff11a63424ea68c9d61764a3235c2,
title = "Ionic Liquid-Solute Interactions Studied by 2D NOE NMR Spectroscopy",
abstract = "Intermolecular interactions between a Ru2+(bpy)3 solute and the anions and cations of four different ionic liquids (ILs) are investigated by 2D NMR nuclear Overhauser effect (NOE) techniques, including {1H-19F} HOESY and {1H-1H} ROESY. Four ILs are studied, each having the same bis(trifluoromethylsulfonyl)amide anion in common. Two of the ILs have aliphatic 1-alkyl-1-methylpyrrolidinium cations, while the other two ILs have aromatic 1-alkyl-3-methylimidazolium cations. ILs with both shorter (butyl) and longer (octyl or decyl) cationic alkyl substituents are studied. NOE NMR results suggest that the local environment of IL anions and cations near the Ru2+(bpy)3 solute is rather different from the bulk IL structure. The solute-anion and solute-cation interactions are significantly different both for ILs with short vs long alkyl tails and for ILs with aliphatic vs aromatic cation polar head groups. In particular, the solute-anion interactions are observed to be about 3 times stronger for the cations with shorter alkyl tails relative to the ILs with longer alkyl tails. The Ru2+(bpy)3 solute interacts with both the polar head and the nonpolar tail groups of the 1-butyl-1-methylpyrrolidinium cation but only with the nonpolar tail groups of the 1-decyl-1-methylpyrrolidinium cation. (Chemical Equation Presented).",
author = "Sufia Khatun and Ed Castner",
year = "2015",
month = "7",
day = "23",
doi = "10.1021/jp509861g",
language = "English",
volume = "119",
pages = "9225--9235",
journal = "Journal of Physical Chemistry B Materials",
issn = "1520-6106",
publisher = "American Chemical Society",
number = "29",

}

TY - JOUR

T1 - Ionic Liquid-Solute Interactions Studied by 2D NOE NMR Spectroscopy

AU - Khatun, Sufia

AU - Castner, Ed

PY - 2015/7/23

Y1 - 2015/7/23

N2 - Intermolecular interactions between a Ru2+(bpy)3 solute and the anions and cations of four different ionic liquids (ILs) are investigated by 2D NMR nuclear Overhauser effect (NOE) techniques, including {1H-19F} HOESY and {1H-1H} ROESY. Four ILs are studied, each having the same bis(trifluoromethylsulfonyl)amide anion in common. Two of the ILs have aliphatic 1-alkyl-1-methylpyrrolidinium cations, while the other two ILs have aromatic 1-alkyl-3-methylimidazolium cations. ILs with both shorter (butyl) and longer (octyl or decyl) cationic alkyl substituents are studied. NOE NMR results suggest that the local environment of IL anions and cations near the Ru2+(bpy)3 solute is rather different from the bulk IL structure. The solute-anion and solute-cation interactions are significantly different both for ILs with short vs long alkyl tails and for ILs with aliphatic vs aromatic cation polar head groups. In particular, the solute-anion interactions are observed to be about 3 times stronger for the cations with shorter alkyl tails relative to the ILs with longer alkyl tails. The Ru2+(bpy)3 solute interacts with both the polar head and the nonpolar tail groups of the 1-butyl-1-methylpyrrolidinium cation but only with the nonpolar tail groups of the 1-decyl-1-methylpyrrolidinium cation. (Chemical Equation Presented).

AB - Intermolecular interactions between a Ru2+(bpy)3 solute and the anions and cations of four different ionic liquids (ILs) are investigated by 2D NMR nuclear Overhauser effect (NOE) techniques, including {1H-19F} HOESY and {1H-1H} ROESY. Four ILs are studied, each having the same bis(trifluoromethylsulfonyl)amide anion in common. Two of the ILs have aliphatic 1-alkyl-1-methylpyrrolidinium cations, while the other two ILs have aromatic 1-alkyl-3-methylimidazolium cations. ILs with both shorter (butyl) and longer (octyl or decyl) cationic alkyl substituents are studied. NOE NMR results suggest that the local environment of IL anions and cations near the Ru2+(bpy)3 solute is rather different from the bulk IL structure. The solute-anion and solute-cation interactions are significantly different both for ILs with short vs long alkyl tails and for ILs with aliphatic vs aromatic cation polar head groups. In particular, the solute-anion interactions are observed to be about 3 times stronger for the cations with shorter alkyl tails relative to the ILs with longer alkyl tails. The Ru2+(bpy)3 solute interacts with both the polar head and the nonpolar tail groups of the 1-butyl-1-methylpyrrolidinium cation but only with the nonpolar tail groups of the 1-decyl-1-methylpyrrolidinium cation. (Chemical Equation Presented).

UR - http://www.scopus.com/inward/record.url?scp=84938117966&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=84938117966&partnerID=8YFLogxK

U2 - 10.1021/jp509861g

DO - 10.1021/jp509861g

M3 - Article

AN - SCOPUS:84938117966

VL - 119

SP - 9225

EP - 9235

JO - Journal of Physical Chemistry B Materials

JF - Journal of Physical Chemistry B Materials

SN - 1520-6106

IS - 29

ER -